Dissociation between affective experience and motivated behaviour in schizophrenia patients and their unaffected first-degree relatives and schizotypal individuals.

BACKGROUND

The neuropsychological origins of negative syndrome of schizophrenia remain elusive. Evidence from behavioural studies, which utilised emotion-inducing pictures to elicit motivated behaviour generally reported that that schizophrenia patients experienced similar affective experience as healthy individuals but failed to translate emotional salience to motivated behaviour, a phenomenon called emotion-behaviour decoupling. However, a few studies have examined emotion-behaviour decoupling in non-psychotic high-risk populations, who are relatively unaffected by medication effects.

METHODS

In this study, we examined the nature and extent of emotion-behaviour decoupling in in three independent samples (65 schizophrenia patients v. 63 controls; 40 unaffected relatives v. 45 controls; and 32 individuals with social anhedonia v. 32 controls). We administered an experimental task to examine their affective experience and its coupling with behaviour, using emotion-inducing slides, and allowed participants to alter stimulus exposure using button-pressing to seek pleasure or avoid aversion.

RESULTS

Schizophrenia patients reported similar affective experiences as their controls, while their unaffected relatives and individuals with high levels of social anhedonia exhibited attenuated affective experiences, in particular in the arousal aspect. Compared with their respective control groups, all of the three groups showed emotion-behaviour decoupling.

CONCLUSIONS

Our findings support that both genetically and behaviourally high-risk groups exhibit emotion-behaviour decoupling. The familial association apparently supports its role as a putative trait marker for schizophrenia.